Can’t find a solid steel 1-1/4 in axle

Solomonster212

High Compression Member
Messages
234
Reaction score
12
Location
Hoover, Alabama
I bought mine from Amazon. But it shipped from Gopowersports. I guess I could have ordered it directly from there...

Just checked, it's "No longer available"
 
Messages
71
Reaction score
24
Location
NW Arkansas
No way! That's craziness!

I know... Its a heavy kart pretty much a buggy with 24s and a motorcycle engine and its pretty wide but still I thought I would be able to get atleast a few runs in.

---------- Post added at 04:13 PM ---------- Previous post was at 03:59 PM ----------

It's for a 60hp engine so a 1" might not be able to hold up. But it appears as though, keys are breaking at 30hp engines so about 40ft/lbs of torque. Keys are going to be the weak point. If there's an easy way to get splined hubs for sprockets and rotors, should be a non-issue.

Appears I may have found an answer. https://www.rollerchain4less.com/splined-bore-weld-on-hub

Its a ninja 500 engine so it doesn't make tons of torque only around 32ft pounds if I recall correctly. Which is honestly about the right amount of usable torque for offroad. And as a bonus it hasn't sheared any keys yet. It still spins the 24s on command but its pretty controllable. I wen't up a few teeth from stock on the rear but the thing still hits high 40s in second gear! the main reason I want the thicker axle is mostly due to having a couple hundred extra pounds over the rear axle.
 

ol'joe

Member
Messages
108
Reaction score
6
Location
New Mexico desert
If anybody would like, I can check around with my steel suppliers for 1 1/4" cold roll round bar. I had an issue with the same size square stock not long ago, and was told the mills were no longer rolling it so it was no longer available and I have been having to mill down 1 1/2" to size ever since.

If the same issue exists for the round stock, I DO have some rather rough 1 3/16" round bar but I dunno if any of the sprockets or hubs are available in that size. Next best bet would be to make step axles from 1 1/2" and turn a step on each end for the wheels with one step longer to accommodate the sprocket. Seems like the long way around, but would give you an even heavier axle with the exception of the smaller steps and would tend to reduce any whip in the axle anyhow.

It is just possible there are some grades like 1045 out there milled in that diameter that would be better than the usual cold roll, so that maybe should be checked on, too.

In any event, looks like some machine work is going to be required to get there from here, I I might be able to provide that fairly reasonable if folks are intent on going that direction. I have been laying back to see if anybody else solved this, so if anybody has or nobody wants to proceed, just say so and I will shattup….. :) …..Joe
 

ol'joe

Member
Messages
108
Reaction score
6
Location
New Mexico desert
Well, there y'go ! How long was it? It will be more difficult to machine than the 1020, but dang sure harder to destroy, too.

It may be available cheaper from some of the steel-only suppliers, too....Joe
 

Kartorbust

Inmate #627
Messages
4,465
Reaction score
916
Location
Utica, NE
If it's easier for some to just buy the round stock, I wonder what the cost will be to have it cut for a keyway or splines?
 

SquidBonez

Active member
Messages
512
Reaction score
132
Location
New Jersey, USA
It's for a 60hp engine so a 1" might not be able to hold up. But it appears as though, keys are breaking at 30hp engines so about 40ft/lbs of torque. Keys are going to be the weak point. If there's an easy way to get splined hubs for sprockets and rotors, should be a non-issue.

Appears I may have found an answer. https://www.rollerchain4less.com/splined-bore-weld-on-hub

Couldn't you just weld the key/sprocket in place? I think that's what RBG ended up doing. Much stronger that way. If you get a split sprocket w/hub it will still allow for gear ratio changes but you won't be able to change the position of the sprocket hub on the axle unfortunately. So make sure you got that alignment CORRECT the first time! As for axle material, stay away from the 1-1/4" aluminum axle. I was originally considering aluminum for my next build but decided against it. Granted, I'll only be running about 20 horsepower versus your 60, but simply since it's an off road kart that will be taking bumps & jumps, steel is the way to go. The 1-1/4" steel keyed shaft seems like the best bet. Just tap out the ends of the axle so you can use a bolt w/ a large washer (and maybe a lock washer just for added peace of mind) to hold your hubs on. Here are some hubs that would work for a 4x4 bolt pattern: https://www.bmikarts.com/4-x-4-Billet-Aluminum-Wheel-Hub-1-14-Bore_p_1647.html
 

Kartorbust

Inmate #627
Messages
4,465
Reaction score
916
Location
Utica, NE
Couldn't you just weld the key/sprocket in place? I think that's what RBG ended up doing. Much stronger that way. If you get a split sprocket w/hub it will still allow for gear ratio changes but you won't be able to change the position of the sprocket hub on the axle unfortunately. So make sure you got that alignment CORRECT the first time! As for axle material, stay away from the 1-1/4" aluminum axle. I was originally considering aluminum for my next build but decided against it. Granted, I'll only be running about 20 horsepower versus your 60, but simply since it's an off road kart that will be taking bumps & jumps, steel is the way to go. The 1-1/4" steel keyed shaft seems like the best bet. Just tap out the ends of the axle so you can use a bolt w/ a large washer (and maybe a lock washer just for added peace of mind) to hold your hubs on. Here are some hubs that would work for a 4x4 bolt pattern: https://www.bmikarts.com/4-x-4-Billet-Aluminum-Wheel-Hub-1-14-Bore_p_1647.html

Sprockets wear out and cutting welds takes for freaking ever. I agree with everyone, welding sprockets on axles is a really stupid idea.
 

ol'joe

Member
Messages
108
Reaction score
6
Location
New Mexico desert
Don't forget that 1045 steel is not high carbon, but neither is it low carbon. the rapid heating and cooling that welding entails can pretty dang easily harden the spot where you weld it, making it brittle. Welds that go AROUND a shaft are really common causes of breaking the shaft right at that exact spot.

I know that machining steel is expensive but if all you need is a keyway and you know right where you need it instead of having to go full length, that operation should be quite reasonable in relative terms. The cut will take far less time than finding the cutter, putting it in the mill, adjusting for position....plus you will have as good a setup as can be had...Joe
 

SquidBonez

Active member
Messages
512
Reaction score
132
Location
New Jersey, USA
Sprockets wear out and cutting welds takes for freaking ever. I agree with everyone, welding sprockets on axles is a really stupid idea.
True, but like I said, the issue of changing out sprockets can be avoided if you just weld the sprocket HUB to the axle (not the sprocket itself), and bolt the sprocket to the hub. That way you can still swap sprockets without worrying about the keyway issue. Again, I think that's what RBG does on higher power builds.
 
Messages
71
Reaction score
24
Location
NW Arkansas
I am not welding anything I have never had a key break I just use a long keyway and split steel lock collars on each side of the key works like a charm. This axle is an absolute beast but it cost me nearly $200 all in after having the machine shop cut it and thread it. Called a few places and they all charged me for 1 hour minimum which is a joke because it only took the guy 35 minutes. Either way I know it wont be getting replaced EVER so im not worried about it. So if anyone is planning to do this its probably better to just buy the round and have the shop machine the keyway since you get charged for an hour anyway.
 

ol'joe

Member
Messages
108
Reaction score
6
Location
New Mexico desert
Agreed, and if you break or warp an axle from welding on it, you will have already paid for it once.Sounds like some of you guys need to pop for modest sized metal lathes and milling machines. With the right setup you CAN even mill a keyway on a lathe, but once you own the lathe you WILL want the mill. They will change your whole life if you do much fabrication. I might have mine buried with me :) …..Joe
 
Messages
71
Reaction score
24
Location
NW Arkansas
Agreed, and if you break or warp an axle from welding on it, you will have already paid for it once.Sounds like some of you guys need to pop for modest sized metal lathes and milling machines. With the right setup you CAN even mill a keyway on a lathe, but once you own the lathe you WILL want the mill. They will change your whole life if you do much fabrication. I might have mine buried with me :) …..Joe
How much for a decent lathe / mill setup?
 

ol'joe

Member
Messages
108
Reaction score
6
Location
New Mexico desert
Boy! a lot depends on where you are and how long and hard you are willing to look. I will do a few paragraphs on buying used machine tools, since I have been down that road a LOT of times before, but you can find real screaming deals unless you are desperate and in a hurry.

If you find a metal lathe that is in reasonable shape in the 12" swing neighborhood and 5 feet long between centers, you will have gotten a good deal if you get it for $1000 or less, used. They are really scarce here in the Southwest, but back in the rust belt they should be plentiful. If the distance between centers is shorter, the hole in the spindle needs to be larger than the biggest axle you might ever want to turn, so you can feed it in through the hole. If you have to turn it between centers and your machine is too short, you are outa luck. You can begin a search by going to Craigslist in surrounding cities and typing in "lathe" in the search box. Start reading down the list and eliminating all of the brake lathes and wood lathes, study what's left.

Then do the same with "milling machine". You can work with either a verticle or horizontal mill, which means you may find one that the perfectionists and" vertical mill only" guys may spurn. Possibly cheaper. People also are prone to trade them for stuff if they cannot get the cash out of them.

I know it sounds like a lot of money, but you can do work for your buddies at $50 an hour, be the cheapest guy in town. Most poplar guy, too :)

You'd need to study up a bit and make sure you got an ENGINE lathe with threading capabilities, get it checked out a bit, but not hard to learn the basic operations for most folks....Joe
 

SquidBonez

Active member
Messages
512
Reaction score
132
Location
New Jersey, USA
I am not welding anything I have never had a key break I just use a long keyway and split steel lock collars on each side of the key works like a charm. This axle is an absolute beast but it cost me nearly $200 all in after having the machine shop cut it and thread it. Called a few places and they all charged me for 1 hour minimum which is a joke because it only took the guy 35 minutes. Either way I know it wont be getting replaced EVER so im not worried about it. So if anyone is planning to do this its probably better to just buy the round and have the shop machine the keyway since you get charged for an hour anyway.
Sounds good. I was unaware that welding the axle could warp it like ol'joe said. Make sure to post build updates, we always like to see new projects!
 

ol'joe

Member
Messages
108
Reaction score
6
Location
New Mexico desert
Lots of strange stuff goes on with ferrous metals. I have seen shafts running 1/8" or more out of line in 4 feet because somebody ran a penetrating weld half way around them.

Then, there is the risk that the hub will be some variety of cast iron or ductile iron that will not weld to steel very well with standard welding rod or wire.

I have not just stood back and watched others make those mistakes, either. I have OWNED a fair number of them myself.. :) I was told at an early age that I have the capability to ruin an good anvil with a rubber hammer....Now, THAT HURT! :) ...Joe
 

Kartorbust

Inmate #627
Messages
4,465
Reaction score
916
Location
Utica, NE
I did have a thought of using two extra collars would help alleviate the problem of keys breaking, but in practice no idea how long it would work. Would be nice to have a lathe to make parts, especially a solid chromoly axle.
 

ol'joe

Member
Messages
108
Reaction score
6
Location
New Mexico desert
Harder to shear a key than one might imagine, especially if everything is tight and they key is steel. The shear strength of steel is about 25000 pounds per square inch and a 4 inch long key that is 1/4" wide and fully supported along it's length in the steel keyway is exactly one square inch of steel that would have to be sheared to break it.

If it were loose fitting and the keyway were constantly slamming back and forth on the key it would take a lot LESS energy because of the impacts, but I am pretty sure that any steady pull that would shear a full one wquare inch of steel key would twist off the axle before the key sheared. I have no formal specification to back up that opinion about twisting off the axle, but I would wager half my weekly allowance from my wife that I am correct :) …..Joe
 
Top